What is a Decree of Nullity?

A decree of nullity means a marriage entered into between two parties is void. It is the court’s way of dissolving a legal relationship that technically did not exist in the first place. There are a number of circumstances under which a marriage can be declared void. These are set out under Section 23B of the Marriage Act 1961.

1. Where one of the parties to the marriage is lawfully married to another person

It is irrelevant whether the marriage occurred in a different country, or you believe the person to be dead or missing. In the event a person is lawfully married to another and that person enters into another marriage with a second person, then the second marriage is at risk of being void.

2. Where the relationship is a “prohibited relationship”

Any marriage between siblings (whether full blood or half-blood), ancestors or descendants is considered a “prohibited relationship” according to the Act, and the marriage could be declared void and a nullity. This rule also applies to adopted family.

3. Failing to comply with the legislation

There are many requirements that each person to the marriage must comply with before the marriage can be solemnised. According to s 48 of the Marriage Act, the marriage may be void where the parties have not complied with specific legislative provisions, for example:

  • Failing to have two witnesses over the age of 18;
  • Where the celebrant is not authorised by law (however if both parties believe the celebrant has the requisite authorisation to solemnise the marriage, then the ceremony is deemed sufficient);
  • Failing to provide a proper notice under the Act; and
  • Making a false declaration as to one’s conjugal status, and/or belief that there is no legal impediment to the marriage.

It is important to ensure that the specific legislative provisions are followed and generally this process will be guided by your marriage celebrant.

4. Where there was no real consent

If it can be established that the consent to the marriage was obtained by fraud or duress, or one party was mistaken as to the other party’s identity, the marriage might be declared void.

5. Where either party was not of “marriageable age”

In order to be married in Australia each party must be at least 18 years’ old. A person between the age of 16 and 18 may apply to the Court for permission to marry, however permission is only granted in exceptional circumstances. In addition, the minor will need consent of their parents in order to be married.

If you require legal advice or representation in any legal matter, please contact Armstrong Legal.


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